The design of a printed circuit board (wiring board) is often carried out by the use of a printed circuit board CAD (Computer Aided Design) device using a computer (for example, Patent Document 1). Many portions of the design of a printed circuit board using a CAD device are automated, but the appropriate design thereof can often be carried out by only an expert designer.
In design of a printed circuit board of a high-frequency circuit, inter-wiring interference often has a great influence on a transmission characteristic. However, to compute the amount of inter-wiring interference, it is required to calculate characteristics of the wirings using complex computations based on the electromagnetic field analysis. Accordingly, unlike the analysis of a simple textbook wiring model, it is often difficult to consider the amount of inter-wiring interference in actually designing complex wirings. It is often impossible to make the computation within the finite operating time.
Therefore, the consideration of the amount of inter-wiring interference often depends on an expert designer's sense, not the electromagnetic field analysis, or often depends on trial and error without considering the amount of inter-wiring interference.
Patent Document 1: JP-A-10-214281